Austrian chancellor Sebastian Kurz repeatedly referred to the foiled plot against the Organisation for the Prohibition of Chemical Weapons when he spoke to reporters about Austria’s suspected Russian agent.

“Based on the information we have, but also because of recent events for example in the Netherlands, we can very much assume at the moment that our suspicion will be confirmed,” he said.

The alleged mole is a recently retired colonel who was believed to have spied for Moscow from the 1990s until this year, the Austrian leader said.

Image:Austria was did not expel any Russian diplomats over the Skripal poisonings

Weapons systems and migration into Europe were among the issues the suspected spy or his handlers were said to have been interested in.

“If the suspicion is confirmed, such cases… do not improve relations between Russia and the European Union,” Mr Kurz said, without naming the suspect.

The case has been referred to prosecutors and the former colonel has been questioned, according to Reuters.

0:54

Video:Inside Russia’s largest war games

The move is particularly notable because Austria has close ties to Russia, which are understood to have caused concern for a number of countries, including the UK.

Austria was in the minority of EU countries that did not expel any Russian diplomats over the poisoning of the Skripals in March and the chancellor has met twice with the Russian president since the attack.

In a possible shift in attitude, Austria’s foreign minister has cancelled a planned trip to Moscow over the suspected spy case and summoned the Russian charge d’affaires since the ambassador is outside the country.

“For the moment we are demanding transparent information from the Russian side,” Mr Kurz said.

Russia reacted with indignation to the allegation.

Foreign minister Sergei Lavrov said he was “unpleasantly surprised” and claimed Moscow knew nothing about the retired officer, local news agencies reported.